Segmented Turning Angle For a 12 Segment Ring
15°
- 12-segment ring
Methodeach segment's miter angle = 180 / segment count — the same flat-frame formula applied around a full ring.
This is the miter angle per segment edge; stave height and outer diameter are separate calculations this page does not cover.
Each segment in a 12-segment turning ring is cut at 15° — the default segment count most segmented-turning books and tutorials teach first, before anyone starts customizing the number of staves per ring.
Why this one specifically
Twelve is the segment count segmented turning treats as a baseline the way woodworking treats a 2x4 as a default stud size: it's round enough to look genuinely circular once turned, it divides cleanly by common multiples for building multi-layer bowls with rotated segment patterns between rings, and 15° is precise enough for most benchtop miter saws' scales to hold reliably across all twelve joints. Beginners are usually pointed at 12-segment rings first for exactly this reason — the geometry is forgiving and the angle is one most saws already have a stop for.
What moves the number
This is fixed by segment count alone; it says nothing about stave height, ring diameter or how many stacked rings a bowl needs. Species contrast matters more here than in flat box work, since a segmented ring's visual appeal usually depends on alternating light and dark woods around the circle, which this angle figure doesn't account for.